>> reporter: often inspired by the sandy hook school shooting donors are giving to a gun buy back fund. $40,000 in public donations. enabling marin to buy guns, no names, no questions asked. >> thank you for getting those guns out of your house. god bless you. >> if they want to turn in three gun, they'll get paid on the spot. >> reporter: each gun is worth $100, $200 if it's a semi automatic. >> this is what you can do for mankind. >> reporter: we found marin residents enthusiastic and optimistic.